We’re saluting the five most popular songs in the Billboard Hot 100 Pop Singles Chart, for the week ending September 24, 2016. The countdown catches its breath after a few active weeks, so you get a chance to hear all of last week’s hits again. Number 5: The Chainsmokers Featuring Daya "Don't Let Me Down" The Chainsmokers and Daya start us off, as “Don’t Let Me Down” holds at number five. The single first came out way back in February. Since then, it has gone double platinum in the United States, signifying sales of more than two million. Group member Andrew Taggart says he created the song on a flight, but didn’t choose a vocalist until he heard Daya’s 2015 debut single “Hide Away.” The Chainsmokers sure aren’t hiding this week…more about that later. Number 4: Sia Featuring Sean Paul "Cheap Thrills" Sia and Sean Paul spend another week in fourth place with their former champ “Cheap Thrills.” Earlier this month, Sia went on Twitter to declare that she’d been sober for six years. Sia has spoken about her substance abuse issues, and thanked all of those who supported her in her struggles. Number 3: Major Lazer Featuring Justin Bieber & MO We have a change in third place, where Major Lazer, Justin Bieber, and MO step back a slot with “Cold Water.” Major Lazer is here in the United States for three festivals in New York City, Las Vegas, and Austin, Texas. Justin Bieber is on the home stretch of his world tour with U.K. and European dates continuing through late November, while MO is also crisscrossing the globe: she’ll hit Europe, the U.K., and North America before wrapping things up in early December. Number 2: Twenty One Pilots "Heathens" As for twenty one pilots, they’re right here, as “Heathens” gets serious in second place. Group member Josh Dun says he was raised in a strict household, and as a boy in Columbus, Ohio would hide his rock CDs from his parents. Number 1: The Chainsmokers "Closer" As promised, The Chainsmokers are back…and they haven’t moved from atop the list. They performed their current hit at the MTV Awards, but aren’t happy about how it turned out. Group member and singer Drew Taggart claims that MTV set them up to fail. He tells Billboard that his vocal track was badly mixed…and reveals that nearly all the other performers on the show lip-synced. No faking here: we want you back next week for more hits!